Why would you want to put a telescope into an aircraft for astronomical observations? That presents considerable challenges.
Aircraft are expensive to buy and to operate.
They vibrate and bounce around during turbulence. This makes pointing a telescope at astronomical targets very difficult.
You've got to build a door into the aircraft frame that opens during observations so the telescope has a clear view (you can't do it very well through a window). This open door creates all sorts of problems. Just imagine opening a window of your car while traveling at jet aircraft speeds. The turbulence and noise would be horrendous. The aircraft might even become unstable.
So why go to all of this trouble?
The answer is, to get above most of the earth's atmosphere and get a clear view of the sky. Our atmosphere blocks much of the radiation that comes to us from space.
